textproduct: Rapid City

KEY MESSAGES

- High winds move through the area Thursday with gusts in excess of 60 mph for much of the area. Strongest winds across western South Dakota plains where gusts to 70-80+ mph are expected.

- Strong prefrontal winds and low relative humidity will result in critical fire weather conditions across the southern half of the forecast area Thursday.

- Multiple rounds of light rain/snow Thursday night through Sunday. Best chances for accumulating snow will be in the Black Hills and along and north of I-90, where 4-6+" of snow is possible.

DISCUSSION

(Tonight Through Wednesday) Issued at 1028 PM MDT Wed Mar 11 2026

Upper level analysis shows subtle shortwave ridging over the Northern Rockies with influx of upper level moisture streaming into the Northern Plains. High level clouds will continue to advect into the region overnight as potent clipper system arrives Thursday afternoon. Light rain/snow chances possible across NW SD through the morning, although little to no accumulation expected.

The main forecast concern - very strong winds to develop Thursday. Strong west-southwesterly winds will increase rapidly ahead of a strong cold front. The front will surge through the area from NW to SE in the afternoon and evening. All the ingredients are there for very strong winds Thursday afternoon and evening: 5-7 mb 3hr pressure rises + strong cold air advection behind the front + steep low level lapse rates + 70-80 knot winds atop the mixed layer. These ingredients will overlap most favorably from NW SD into the western SD plains where gusts to 70-80+ mph are expected. Winds will diminish after 7-9pm MDT.

Attention then turns to precipitation chances overnight Thursday through the weekend. Strong upper level flow will remain entrenched across the Northern Plains with prolonged midlevel frontogenesis, supporting a longer duration rain/snow event. The surface baroclinic zone is forecast to hug the southwestern 1/3 of the forecast area, although confidence is low on exact placement and subsequent low- level thermal profiles. However, accumulating snow probabilities continue to increase across the northern 2/3rds of the CWA with NBM probs >6" of snow ~80%+ in the Black Hills and ~45-60% along and north of I-90 on the WY and SD plains. Snow timing (day vs. night) and location of baroclinic zone will be crucial to analyze with future forecast packages.

AVIATION

(For the 06Z TAFS Through 06Z Thursday Night) Issued At 1144 PM MDT Wed Mar 11 2026

Breezy southwest winds will develop before sunrise this morning, then shift to northwest after 19-21z. Gusts to 40-50 knots are expected across the NE WY/western SD plains. The strongest wind gusts over NW SD may reach over 60kt.

Rain and snow showers will also develop across the area today and tonight, but overall VFR conditions are still expected. However, local MVFR/IFR conditions are possible in any heavier precipitation, especially from the Black Hills to the NE WY plains.

FIRE WEATHER

Issued At 1028 PM MDT Wed Mar 11 2026

Warm, dry, and very windy conditions will support widespread elevated to critical fire wx Thursday afternoon - a Red Flag Warning has been issued for portions of the NE WY plains into the southwestern and western South Dakota plains. While some areas may not quite reach critical RH thresholds (less than 15%), especially if thicker cloud cover lingers, very strong prefrontal winds will result in critical conditions.

Temperatures will warm into the 50s to near 70 on the plains with afternoon RHs ranging from around 18-25% across portions of the NE WY plains and from the Meade County plains and southward. West- southwesterly winds will increase Thursday morning with gusts of up to to 40-50 mph across much of the western SD plains by late morning. Winds will shift to the west and then northwest in the afternoon hours as the front moves through. The winds behind the front are expected to be stronger with sustained winds of 30-45 mph, gusting to 60 to 70 over much of the area with gusts of up to 80 mph possible over the western SD plains.

UNR WATCHES/WARNINGS/ADVISORIES

SD...High Wind Warning from 9 AM MDT /10 AM CDT/ to 9 PM MDT /10 PM CDT/ Thursday for SDZ001-002-012>014-024>032-041>044-046- 047-049-072>078. Red Flag Warning from 11 AM MDT /noon CDT/ to 7 PM MDT /8 PM CDT/ Thursday for SDZ321-322-324>326-329-331>335. WY...High Wind Warning from 9 AM to 9 PM MDT Thursday for WYZ054>060. Red Flag Warning from 11 AM to 7 PM MDT Thursday for WYZ315-317.